This invention relates to a combination book binding machine with a plastic coil forming machine, whereby a plastic spiral coil is formed at a first raised temperature, then cut to a length sufficient for the plastic coil to bind a book, cooled and then advanced toward a receiving coil conveyor of a coil binding machine, for binding the book with a plastic coil formed at the lowered cooled temperature.
While most of the prior art in the field of spiral binding apparatus relates to the use of metallic wire spirals, two patents specifically relate to the use of plastic spirals. U.S. Pat. No. 2,638,609 of Penner describes a machine for binding books with special features for aligning the perforations of a sheaf of papers to be bound and to confine the travel of the plastic spiral binding material. U.S. Pat. No. 4,249,278 of Pfaffle describes a machine for spiral binding which feeds plastic thread from a bulk spool, softens the thread, winds it on a mandrel to form a spiral, cools it to harden and then feeds the rigid spiral into a perforated sheet group.
Pfaffle ""278 integrates the process of the forming of plastic spiral binding coils from plastic thread with that of a binding machine to produce an end product of spiral bound books. Plastic thread is pulled from a spool, preheated, wound around a mandrel in a heated zone, continuously fed into a cooling sleeve for rapid cooling by exposure to a blast of cold air generated by a vortex cooler and then the spiral is fed into the binding machine. However, in Pfaffle ""278 the plastic coil material of polyvinyl-chloride (PVC) can become brittle by the rapid cooling, since it develops voids in its interior. The resulting spiral coil is too brittle to process in a book binding machine since the ends are broken off during the bending process or in early use of the bound books by the ultimate consumer.
Other patents relating to spiral binding machines include U.S. Pat. No. 4,378,822 of Morris which describes a spiral binding machine with a drive component. However, the mandrel of Morris ""822 is fixed, not laterally adjustable as in the present invention, and the mandrel of Morris ""822 has a closed end, which requires pre-feeding of the spiral thereon.
It is an object of this invention to provide a combination plastic spiral coil forming machine that can also accurately insert the plastic spiral coils into a book for binding.
It is yet another object of this invention to provide a spiral bound book with a durable, non-brittle plastic spiral coil.
It further an object of the present invention to provide a transfer conveyor which advances hot, recently formed plastic spiral coils from a forming machine to a spiral insertion machine while cooling the plastic spiral coils.
It is yet another object of this invention to provide an advancement means for accurately transporting a formed plastic spiral coil to its proper position for insertion into the first spiral insertion hole of the book.
It is another object of this invention to be able to quickly cool a formed plastic spiral coil into a solid, flexible state for insertion into spiral insertion holes of a book.
It is another object of this invention to provide a semi-automatic machine of low cost and reliable operation.
It is yet another object of this invention to improve over the disadvantages of the prior art.
In keeping with the objects of the present invention and others which may become apparent, the present invention provides a process for binding books which includes the steps of forming a plastic coil using a plastic spiral forming machine, cooling the plastic coil and inserting the cooled, formed plastic coil into a spiral bindery machine that inserts the cooled, formed coil to bind a book.
After the plastic coil is formed, it is cut and advanced upon a conveyor belt having a plurality of compartments, each holding formed plastic coils. Each of these coils are separately ejected onto each respective compartment, of the plurality of compartments located on the conveyor belt, which is sequentially advanced to expose another compartment of the plurality of compartments on the conveyor belt for the next, formed coil.
While other methods of cooling may be applied to the hot, formed plastic coils, the coils may be cooled by being advanced on the conveyor at a speed sufficient for the temperature of the plastic coil to lower. The advancement of each cooled plastic coil is toward a receiving coil conveyor of the coil binding machine. Then the book is bound with insertion of the lowered temperature plastic coil into the series of edge holes in the book.
While other configurations for the coil advancing conveyor may be used, preferably the linkage conveyor which conveys the plastic coils is a wide belt supported by a stationary horizontal platen, wherein the wide belt has a rigid chain construction with a plurality of fins attached thereto.
A drive pulley communicates with and advances the wide belt and the plurality of fins form the group of separate compartments, which allow the placement of plastic coils therein. For power, a gear motor is electrically connected to a drive pulley. In addition, a motor speed controller is electrically connected to a gear motor, so that the motor speed controller causes the drive pulley to intermittently rotate, thereby intermittently advancing each plastic coil on the belt towards the coil binding machine.
The basic operational concept of the coil insertion portion of the present invention is to use an adjustable speed drive to rotate a spiral coil for a spiral bound book at optimum speed for the diameter of a particular spiral as well as the thickness of the book being bound. This, along with a smooth mandrel with a spiral stabilizing spring, controls the proper feeding of the spiral without the necessity for expensive machined parts to confine the spiral to prevent its distortion.
After the cooled plastic coil is advanced upon the conveyor, the binding machine portion of the present invention spirally binds a sheaf of papers into a book. It clamps together the sheaf of papers making up the book, which book has a plurality of holes in a row adjacent to one edge of the book, to receive the leading edge of the spiral binding element. The machine includes a stationary base which is from one end of the book, and a block slidably mounted on the base, which has an arm extending outwardly.
The arm supports at its distal end thereof a cylindrically shaped mandrel, which is spaced from the slidable block and the bottom edge of the mandrel horizontally in a line corresponding with the row of holes in the book. The arm is attached at its distal end to the mandrel at the proximate end of the mandrel, which faces the row of holes and is spaced apart from the book. The arm is attached to the block at the proximate end, to adjust the distance between the mandrel and the block.
After being advanced on the cooling conveyor, a feeding mechanism feeds the cooled plastic, pre-formed, spiral binding coil element onto the mandrel, from the distal end thereof, which spiral binding element terminates at the proximate end of the mandrel. The leading edge of the binding element faces, and is spaced apart from the book. The internal diameter of the spiral binding element is slightly in excess in size of the outer diameter of the mandrel.
A spring is mounted on the slidable block to engage and to adjustably bias the cooled spiral binding coil on the mandrel upwardly, against the mandrel, so that the upper portion of the binding element is spaced apart from the top of the mandrel.
A wheel, having an outer frictional surface, engages a top outer surface of the cooled spiral binding coil and a motor drives the wheel, to feed the cooled spiral binding coil into the row of holes in the book, for binding the book.
An adjusting mechanism adjusts the position of the block on the base, positioning the mandrel, to obtain proper alignment of the leading edge of the spiral binding element with the row of holes of the book.
To prevent ripping at the edge of the book after it is bound and used, the breach on the book""s cover from the edge of the book to the first spiral coil insertion hole of the book is maximized. This is accomplished by a spreader which increases the breach between adjacent coil segments to align with the predetermined breach from the boundary of the book to the first hole, so that the plastic spiral coil can be accurately inserted into the first spiral insertion hole of the book, and thereafter into the other holes for the book.
For example, while sizes of holes in the book may vary, the holes are typically {fraction (11/64)} inch in diameter, and the measured space between the mid point of each hole to the next adjacent midpoint of the next adjacent hole is about xc2xc inch. Consequently the space between adjacent holes is equal to {fraction (5/64)} inch, which is measured as the distance of xc2xc (or {fraction (16/64)}) inch from hole mid point to hole midpoint, taking into account and deducting the {fraction (11/64)} diameter of each hole.
In the prior art the breach between the first hole and the leading boundary of the pages of the book has also been only about {fraction (5/64)} inch, which is too small a breach to prevent damage by ripping of the cover at the boundary down to the first hole. In the present invention, the breach is increased to about {fraction (3/16)} inch, which is more than double the length of the typical breach on the leading edge of a spiral bound book.
However, to increase the leading edge gap, the distance between adjacent coil segments of a plastic spiral coil must be increased from the typical {fraction (5/64)} inch length to {fraction (3/16)} inch.
This increase in distance is accomplished by a spreader mechanism which contacts and spreads apart the coils of the spiral as they advances from an alignment mandrel to the position where the spiral is enclosed into the leading hole of the book to be bound. The spreader moves apart the first adjacent coil segments from their hole engaging distance of {fraction (5/64)} inch to the increased distance of {fraction (3/16)} inch.
The spreader device has a pair of leading edge spreaders located where the leading boundary edge of the book to be bound is held in place between a pair of comb jaw clamps. Two spreaders are used at the leading edge and a single spreader is used at the trailing edge of the book.
The leading spreader has a body with a slot therein for increasing or decreasing the position of the spreader with respect to the edge of the book to be bound with the plastic spiral.
This leading spreader is preferably a one piece metal unit with an arcuate convex edge being provided at the recess to engage and spread apart adjacent segments of the spiral coil as it advances over the breach between the leading boundary edge of the book and the first hole of the book, toward the first leading hole of the book to be bound.
This first spreader is mounted to a combed clamp jaw permanently attached to, or integral with, a top shelf of the spiral binding machine.
A second spreader, namely a side guide spreader, is mounted to an outer pivotal combed clamp jaw, which pivots into position for tightening the book between the two combed clamp jaws.
A trailing spreader guide is provided at the trailing end of the book to spread apart arcuate segments of the spiral coil as it exits the last edge hole at the trailing distal end of the book being bound. The trailing guide spreader is beveled with a contoured end to engage the coils of the spiral as it engages the last trailing hole of the book.
The side guide spreader adjacent to the leading spreader is a single metal piece with an anvil-type blade extending in the direction of the leading spreader. The front of the blade is fixed to a curved pointed edge which is also rounded to engage the spiral without damage. A spiral guidance groove is located on the back edge of the blade of the spreader side guide to engage a single coil of the spiral.
The front leading spreaders combine to spread a single coil of the spiral as it goes into the first edge hole. Guide notches of the combed clamp jaws are utilized at the path of plastic spiral as it moves through the holes in the book being bound. These notches also align with the holes of the book.
After the cooled, formed plastic spiral coil is advanced on the linkage cooling conveyor, a second conveyor at the beginning of the book binding machine portion moves the plastic spiral to the mandrel for its proper position for insertion into the first spiral insertion hole of the book. The second conveyor includes upwardly extending side guide walls which attenuate on either side of the conveyor. A conveyor motor powers the second conveyor belt about a pulley. In a preferred embodiment, the second conveyor belt may be a pair of elastic cables placed parallel to one another, wherein the spiral touches the cables along the edges of the coil surfaces thereof.
The binding machine also optionally has a cutter for cutting. The plastic spiral binding coil is wound on the book at both ends of the book, and bends both ends of the plastic spiral binding coil element on the book.
Preferably, the binding machine portion of the present invention includes a sensor, such as an optical sensor, for signaling that the leading edge of the spiral binding element has been reached.
A positioning mechanism, such as a pneumatically driven mechanism, positions a rotatable wheel for contact with the spiral binding coil. It includes a hydraulic shock absorber for mediating the speed of engagement of the wheel with the spiral binding coil.
Furthermore, optionally the cutter includes a pair of separated cutting members which are spaced apart from each other, and a rotatable arm for engaging the two cutting members and for actuating the cutting and bending action when rotated in one direction. A further member moves the rotatable arm in a second direction.
A control panel is provided for sequencing the steps of binding the book and indicating visually when the cutting and bending of ends is completed, so that the binding action can be repeated for the next subsequent book to be spirally bound.